Carbureter.



R. BJORKLUND.

CARBURETER.

APPLlcATmN HLED FEB. 23, 1915.

Patented-Nov. 23, 1915.

Wesses ROBERT BJORKLUND, 0F WORCESTER, MASSACHSETTS.

CARBURETER.

Specification of Letters Patent.

Patented Nov. 23, 1915.

Application led February 23, 1915. Serial No. 9,875.

To all fr0/wm t may concern Be it known that I, ROBERT BJORKLUND, a subject of the King of Sweden, residing at 'Worcesten in the county of YWorcester and State of liassachusetts, have invented a new and useful Garbureter, of which the following is a specification.

This invention relates to a carbureter for an internal combustionengine and more particularly to improved devices for control-` ling the proportions of the fuel r'and air mixture in such carbureter.

In the operation of an internal combustion engine, the supply of air must necessarily vary with the speed of the engine, and the supply of fuel should also vary in some lixed relation to the supply of air. This relation, however, is not constant as the relative proportions of air and fuel for a given speed are determined in part by temperature and weather conditions, as well as by the quality of the fuel, and by othervariable factors.

lt is the object of my invention to provide improved devices for varying the supply of fuel proportionately with variations in the supply of air; and also to provide for changing the relative proportionsl of fuel and air to correspond to actual conditions of operation.

further object of my invention is to improve the construction of carbureters of the class described and to increase their efflciency, while at the same time attaining simplicity of parts and cheapness of manufacture. j

The features of my invention relate to certain devices, arrangements and combinations of parts which will bevhereinafter described and more particularly pointed out in the appended claims, said'features possessing advantages in simplicity of construction and ease of operation which will be apparent to those skilled in the art.

A preferred form of my invention is shown in the drawings, in which- Figure 1 is a vertical sectional view of a carbureter embodying my invention; Fig. 2 is a transverse sectional view taken along the line 2 2 in Fig. 1. Fig. 3 is a similar view taken along the Vline 3 3 in Fig. 1; Fig. 4- is a side elevation of the inner frame of the carbureter, and Fig. 5 is a detail view to be described.

As shown in the drawings, my improved carbureter comprises a casing 10 having a frame 11 extending upwardly in an inclined position and secured within the casing. The fuel inlet is indicated at 12, the air inlet at 13 and the outlet to the engine cylinder at 14. ln its lower portion the frame 11 is provided with an air inlet passage 15, said passage being open at its upper end as indicated at 15a for the admission of air from the air inlet' 13 and terminating in two branch passages 15b opening into the mixture chamber 15. An adjustable nozzle 17 is mounted to slide in a recess in the lower portion of the frame 11, said nozzle projectinginto the' air inlet passage 15 and being normally forced outward into said recess by a coil spring 18. A nozzleadjusting lever 19 is pivotcd at 20 to the frame 11 and is forked at its lower end to engage a shoulder on the nozzle 17. At its upper end the lever is provided with a cam-shaped portion 21 positioned for engagement by a stud 22 projecting through a slot 23 in the wall of the casing 10 and carried by a ring 24 angularly movable upon the outer surface of said casing. 'With this construction it will be evident that angular movement of the adjusting ring 2a will be effective through the stud 22 to move the lever 19, thus forcing the nozzle 17 rearwardly in its recess. Said recess at its lower end communicates through a passage 25 with a float chamber 26, the flow of fuel to said chamber being controlled by a needle valve 27 `which is opened by a float 28 when the fuel level in the chamber fallsbelow a given point. The Yfloat 28 is mounted upon an arm 29 which is movable about a pivot 30 positioned eccentrically upon a screw stud` 31. The stud 31 is mounted in an extension 32 of the casing 10 and is provided with a knurled head 33 by which it can be adjusted. Angular adjustment of the stud 31 will change the normal fuel level in the chamber 2G. Theraising of the pivot 30 will permit the needle valve 27 to close when the fuel in the chamber 26 has reached a comparatively low level, whereas lowering of the pivotBO will necessitate the raising of the float to a correspondingly higher position before the `valve is free to close. This adjustment of the pivot will be most co1n monly utilized for priming the carbureter when it is necessary to start a cold engine. The head 33 may be provided with stop pins 3a adapted to cooperate with an index finger 35 to indicate the position of the pivot 80.

Tn its upper central portion the frame 11 is cut away as indicated in dotted lines at 11a (Fig. 4) to provide an auxiliary air intive to the closure 38, as previously de-V scribed, provides a fixed initial opening of the nozzleV through which a definite supply of fuel is admitted to the mixing chamber, said fuel being carried into the chamber by the air flowing past said nozzle through the inlet passage 15.Y

The passage 15 is designed to supply the vfull amountV of air Which will be required by vthe'engine When ruiming idle and the nozzle 17 should be adjusted Vby means of the adjusting ring 24 to permit the passage of the suitable amount of fuel for mixture with this amount of air. As the speed of the engine increases an additional amount of air Will be required and this air is admitted through the auxiliary air inlet 11, the suction of the engine causing the flexible valve. member 36V toV be Vforced backward v toward the dotted line position indicated in Fig. 1. As the closure 38 is carried bythe valve member 36, the closure will be simultaneously moved away from the nozzle 17, thus admitting ,an additional amount of gasolene corresponding proportionately to the increased supply of air.l It will be seen that I have thus provided convenient and very simple mechanism for varying the fuel supply proportionately to the air supplied to the mixing chamber.

VIt has been found, as previously explained, that it is necessary to vary the proportions of air and fuel in accordance With the conditions under which the engine is op-V YAYerating Vand for this-purpose I have provided'means -for varying the proportional relation betweenvthe movements of the valve member 36 and the nozzle closure 38. This means comprises a coil spring 40 engaging the valve member 36 at a point above but adjacent the closure'38, and a lever 41 pivoted at 42 to the frame 11 and effective to regulate the pressure of the spring 40. For

the purposes of such regulation the lever 41 is provided with a cam-shaped head 41L positioned for engagement by a stud 42 carried by a ring 43 and extending through a slot 44 near the upper end of the casing 10. The lever 41 may be adjusted by turning the ring 43 in a manner substantially similar to the adjustment of the lever 19 and by such adjustment thetension of the spring 40 may v be increasedA or diminished.

As the tension of the spring 40 is increased the movement of the closure 38 will be decreased relatively to the movement of the valve member 36, thus decreasing the proportion of fuel admitted to the mixing chamber with a given amount of air. I

have thus provided in an exceedingly simple manner for the adjustment of the fuel supply in different proportionate relations to the air supply.Y It should be further noted that the only moving part of my device is the flexible valve member 36 and that the construction of this member avoids the necessity for any bearings o1' sliding or rotating parts.

VIrlaving rthus described my invention it Will be evident that changes and modifications can be made therein by those skilled in the art Without departing from the spirit thereof as set forth in the claims and I do not Wish to be otherwise limited to the details herein disclosed, but

lWhat I claim is z- 1. A carbureter having, in combination, a casing, a frame therein, a mixing chamber having an air inlet thereto, said inlet being constantly open and of fixed area, a nozzle opening into said inlet, means for adjusting said nozzle to admit a definite initial supply of gasolene to the mixing chamber,A an auxiliary air inlet to said chamber normally closed by a movable valve member, means whereby the movement of said valve member will vary the amount of gasolene admitted to the mixing chamber, and manually operable means to vary the effect of said movable valve upon the amount of gasolene admitted to the mixing chamber.

2. A carbureter having, in combination, a casing, a frame therein, a mixing chamber having an air inlet thereto, a nozzle opening into said inlet, a closure for said nozzle, means for adjusting said nozzle relatively to said closure to provide for the admission of a definite initial supply of gasolene, an auxiliary air inlet to said mixing chamber normally closed by a movable valve member, said valve member and said nozzle closure being so connected that movement of said member will cause proportional movements of said closure relatively to said nozzle, and means to vary the relative proportions of said movements.

3. A carbureter having, in combination, a casing, a frame therein, a mixing chamber -havingl an air inlet thereto, a nozzle opening into said inlet, a closure for said nozzle, meansfor adjusting said nozzle relatively to said closure to provide for the admission of a definite initial supply of gasolene, an auxiliary air inlet to said mixing chamber normally closed by a flexible valve member xedly supported at one end on said frame and having the other end free. said closure being carried by said member' and movable therewith to increase or decrease the nozzle opening.

4. A carbureterihaving, in combination, a casing, a frame therein, a mixing chamber having an air inlet'thereto, a nozzle opening into said inlet, a` closure for said nozzle, means for adjusting said nozzle relatively to said closure to provide for the admission of a deiinite initial supply of gasolene, an auxiliary air inlet to said mixing chamber normally closed by a flexible valve member iixedly supported at one end on said frame and having the other end free, said closure being carried by said member and movable therewith to increase or decrease the nozzle opening, and means to vary the proportional movements of said closure relatively to the movements of the free end of said member.

5. A carbureter having, in combination, a casing, a frame therein, a mixing chamber having an air inlet thereto, a nozzle opening into said inlet, a closure for said nozzle, means for adjusting said nozzle relatively to said closure to provide for the admission of a deiinite initial supply of gasolene, and an auxiliary air inlet to said mixing chamber normally closed by a movable valve member, said member comprising a flat spring plate xed at one end to said frame and having the nozzle closure mounted thereon, movement of the free end of said plate causing a corresponding but proportionately reduced movement of said closure.

6. A carbureter having, in combination, a casing, a frame therein, a mixing chamber having an air inlet thereto, a nozzle opening into said inlet, a closure for said nozzle, means for adjusting said nozzle relatively to said closure to provide for the admission of a definite initial supply of gasolene, an auxiliary air inlet to said mixing chamber normally closed by a movable valve member, said member comprising a flat spring plate fixed at one endto said trame and having the nozzle closure mounted thereon, movement oii the free end of said plate causing a corresponding but proportionally reduced movement of said closure, and means to vary the relative proportions of the movements of said plate and closure.

7. A carbureter having, in combination, a casing, a frame therein, a mixing chamber having an air inlet thereto, al nozzle opening int-o said inlet, a closure for said nozzle, mea-ns for adjusting said nozzle relatively to said closure to provide for the admission of a definite initial supply of gasolene, an auxiliary air inlet to said mixing vchamber normally closed by a movable valve member, said member comprising a flat spring plate iixed at one end to said frameV and having the nozzle closure mounted thereon, movement of the free end of said plate causing a corresponding but proportionally reduced movement of said closure, a spring engaging said plate adjacent said closure, and means to vary the pressure of said spring on said plate, thereby varying the relative proportional movements of said plate and closure.

8. A carbureter having, in combination, a casing, a frame therein, a mixing chamber having an air inlet thereto :termed in said iframe, a nozzle opening into said inlet, a closure for said nozzle, means for adjusting said nozzle relatively to said closure to provide for the admission oi a definite initial supply of gasolene, an auxiliary air inletto said mixing chamber normally closed by a .movable valve member, said member comprising a flat spring plate fixed at one end to said trame and having the nozzle closure mounted thereon, movement of the ree end of said plate causing a corresponding but proportionally reduced movement of said closure, a spring engaging said plate between said closure and the free end of said plate, a lever pivoted to said iframe and engaging one end of said spring, a ring supported by and angularly movable upon said casing, and connections between said ring and said lever whereby angular movement of said ring is eil'ective to vary the pressure of said spring.

9. A carbureter having, in combination, a casing, a springpressed nozzle movably supported therein, a closure for said nozzle, an adjustable stop for positioning said nozzle, a lever supporting said stop, and means comprising a ring angularly movable on the casing for moving said lever to adjust said noz zle relatively to said closure.

l0. A carbureter having, in combination, a casing, a nozzle movably mounted therein, a ring angularlyadjustable on said casing and connections from said ring to said nozzle, whereby angular adjustment of said ring is effective to vary the position of said nozzle, a movable closure for said nozzle and an auxiliary valve member supporting said closure, a second ring angularly adjustable on said casing, and connections from said second ring to said valve member whereby angular adjustment of said second ring is eEective to vary the proportional movements of said valve member and closure.

llO

ln testimony whereof I have hereunto set my hand, in the presence of two subscribing witnesses.

ROBERT BJGRKLUND.

Witnesses:

CHAS. T. HAWLEY, C. Fonnns'r WESSON.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

